linux/drivers/gpu
Zhao Yakui 86e437f077 ACPI: Add the reference count to avoid unloading ACPI video bus twice
Sometimes both acpi video and i915 driver are compiled as modules.
And there exists the strict dependency between the two drivers.
The acpi video bus will be unloaded in course of unloading the i915 driver.
If we unload the acpi video driver, then the kernel oops will be triggered.

Add the reference count to avoid unloading the ACPI video bus twice.
The reference count should be checked before unregistering the acpi video bus.
If the reference count is already zero, it won't unregister it again.
And after the acpi video bus is already unregistered, the reference count
will be set to zero.

http://bugzilla.kernel.org/show_bug.cgi?id=13396

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-06-23 23:38:41 -04:00
..
drm ACPI: Add the reference count to avoid unloading ACPI video bus twice 2009-06-23 23:38:41 -04:00
Makefile drm: reorganise drm tree to be more future proof. 2008-07-14 10:45:01 +10:00